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Re: Sextant with an umbrella
From: Luc Van den Borre
Date: 2015 Oct 1, 22:55 +0200
From: Luc Van den Borre
Date: 2015 Oct 1, 22:55 +0200
On 01/10/15 20:32, Frank Reed wrote: > What's going on in this photo? Is the "umbrella" some sort of prismatic > device for backsights?? Is this one of your quizzes where you already know the answer? :) I suppose it's a Blish prism to measure dip, by viewing the horizon behind next to the horizon in front? If that's the case this may well be a picture of the man himself with his invention... There's a photo of Blish on his Wikipedia page, judge yourself: https://en.wikipedia.org/wiki/John_Bell_Blish Patent drawing: http://sextantbook.com/2012/04/ Luc
